/* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-2004 Jean-loup Gailly.
+ * Copyright (C) 1995-2005 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
*
*/
-/* @(#) $Id: deflate.c,v 1.1 2005/06/17 13:54:46 vp153 Exp $ */
+/* @(#) $Id: deflate.c,v 1.2 2008/05/26 19:08:10 vp153 Exp $ */
#include "deflate.h"
const char deflate_copyright[] =
- " deflate 1.2.2 Copyright 1995-2004 Jean-loup Gailly ";
+ " deflate 1.2.3 Copyright 1995-2005 Jean-loup Gailly ";
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
#endif
if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
- strategy < 0 || strategy > Z_RLE) {
+ strategy < 0 || strategy > Z_FIXED) {
return Z_STREAM_ERROR;
}
if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */
s->strm = strm;
s->wrap = wrap;
+ s->gzhead = Z_NULL;
s->w_bits = windowBits;
s->w_size = 1 << s->w_bits;
s->w_mask = s->w_size - 1;
if (length < MIN_MATCH) return Z_OK;
if (length > MAX_DIST(s)) {
length = MAX_DIST(s);
-#ifndef USE_DICT_HEAD
dictionary += dictLength - length; /* use the tail of the dictionary */
-#endif
}
zmemcpy(s->window, dictionary, length);
s->strstart = length;
}
/* ========================================================================= */
+int ZEXPORT deflateSetHeader (strm, head)
+ z_streamp strm;
+ gz_headerp head;
+{
+ if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ if (strm->state->wrap != 2) return Z_STREAM_ERROR;
+ strm->state->gzhead = head;
+ return Z_OK;
+}
+
+/* ========================================================================= */
int ZEXPORT deflatePrime (strm, bits, value)
z_streamp strm;
int bits;
#else
if (level == Z_DEFAULT_COMPRESSION) level = 6;
#endif
- if (level < 0 || level > 9 || strategy < 0 || strategy > Z_RLE) {
+ if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) {
return Z_STREAM_ERROR;
}
func = configuration_table[s->level].func;
return err;
}
+/* ========================================================================= */
+int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
+ z_streamp strm;
+ int good_length;
+ int max_lazy;
+ int nice_length;
+ int max_chain;
+{
+ deflate_state *s;
+
+ if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+ s = strm->state;
+ s->good_match = good_length;
+ s->max_lazy_match = max_lazy;
+ s->nice_match = nice_length;
+ s->max_chain_length = max_chain;
+ return Z_OK;
+}
+
/* =========================================================================
* For the default windowBits of 15 and memLevel of 8, this function returns
* a close to exact, as well as small, upper bound on the compressed size.
if (s->status == INIT_STATE) {
#ifdef GZIP
if (s->wrap == 2) {
+ strm->adler = crc32(0L, Z_NULL, 0);
put_byte(s, 31);
put_byte(s, 139);
put_byte(s, 8);
- put_byte(s, 0);
- put_byte(s, 0);
- put_byte(s, 0);
- put_byte(s, 0);
- put_byte(s, 0);
- put_byte(s, s->level == 9 ? 2 :
- (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
- 4 : 0));
- put_byte(s, 255);
- s->status = BUSY_STATE;
- strm->adler = crc32(0L, Z_NULL, 0);
+ if (s->gzhead == NULL) {
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, 0);
+ put_byte(s, s->level == 9 ? 2 :
+ (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+ 4 : 0));
+ put_byte(s, OS_CODE);
+ s->status = BUSY_STATE;
+ }
+ else {
+ put_byte(s, (s->gzhead->text ? 1 : 0) +
+ (s->gzhead->hcrc ? 2 : 0) +
+ (s->gzhead->extra == Z_NULL ? 0 : 4) +
+ (s->gzhead->name == Z_NULL ? 0 : 8) +
+ (s->gzhead->comment == Z_NULL ? 0 : 16)
+ );
+ put_byte(s, (Byte)(s->gzhead->time & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff));
+ put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff));
+ put_byte(s, s->level == 9 ? 2 :
+ (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
+ 4 : 0));
+ put_byte(s, s->gzhead->os & 0xff);
+ if (s->gzhead->extra != NULL) {
+ put_byte(s, s->gzhead->extra_len & 0xff);
+ put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);
+ }
+ if (s->gzhead->hcrc)
+ strm->adler = crc32(strm->adler, s->pending_buf,
+ s->pending);
+ s->gzindex = 0;
+ s->status = EXTRA_STATE;
+ }
}
else
#endif
strm->adler = adler32(0L, Z_NULL, 0);
}
}
+#ifdef GZIP
+ if (s->status == EXTRA_STATE) {
+ if (s->gzhead->extra != NULL) {
+ uInt beg = s->pending; /* start of bytes to update crc */
+
+ while (s->gzindex < (s->gzhead->extra_len & 0xffff)) {
+ if (s->pending == s->pending_buf_size) {
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ flush_pending(strm);
+ beg = s->pending;
+ if (s->pending == s->pending_buf_size)
+ break;
+ }
+ put_byte(s, s->gzhead->extra[s->gzindex]);
+ s->gzindex++;
+ }
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ if (s->gzindex == s->gzhead->extra_len) {
+ s->gzindex = 0;
+ s->status = NAME_STATE;
+ }
+ }
+ else
+ s->status = NAME_STATE;
+ }
+ if (s->status == NAME_STATE) {
+ if (s->gzhead->name != NULL) {
+ uInt beg = s->pending; /* start of bytes to update crc */
+ int val;
+
+ do {
+ if (s->pending == s->pending_buf_size) {
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ flush_pending(strm);
+ beg = s->pending;
+ if (s->pending == s->pending_buf_size) {
+ val = 1;
+ break;
+ }
+ }
+ val = s->gzhead->name[s->gzindex++];
+ put_byte(s, val);
+ } while (val != 0);
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ if (val == 0) {
+ s->gzindex = 0;
+ s->status = COMMENT_STATE;
+ }
+ }
+ else
+ s->status = COMMENT_STATE;
+ }
+ if (s->status == COMMENT_STATE) {
+ if (s->gzhead->comment != NULL) {
+ uInt beg = s->pending; /* start of bytes to update crc */
+ int val;
+
+ do {
+ if (s->pending == s->pending_buf_size) {
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ flush_pending(strm);
+ beg = s->pending;
+ if (s->pending == s->pending_buf_size) {
+ val = 1;
+ break;
+ }
+ }
+ val = s->gzhead->comment[s->gzindex++];
+ put_byte(s, val);
+ } while (val != 0);
+ if (s->gzhead->hcrc && s->pending > beg)
+ strm->adler = crc32(strm->adler, s->pending_buf + beg,
+ s->pending - beg);
+ if (val == 0)
+ s->status = HCRC_STATE;
+ }
+ else
+ s->status = HCRC_STATE;
+ }
+ if (s->status == HCRC_STATE) {
+ if (s->gzhead->hcrc) {
+ if (s->pending + 2 > s->pending_buf_size)
+ flush_pending(strm);
+ if (s->pending + 2 <= s->pending_buf_size) {
+ put_byte(s, (Byte)(strm->adler & 0xff));
+ put_byte(s, (Byte)((strm->adler >> 8) & 0xff));
+ strm->adler = crc32(0L, Z_NULL, 0);
+ s->status = BUSY_STATE;
+ }
+ }
+ else
+ s->status = BUSY_STATE;
+ }
+#endif
/* Flush as much pending output as possible */
if (s->pending != 0) {
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
status = strm->state->status;
- if (status != INIT_STATE && status != BUSY_STATE &&
+ if (status != INIT_STATE &&
+ status != EXTRA_STATE &&
+ status != NAME_STATE &&
+ status != COMMENT_STATE &&
+ status != HCRC_STATE &&
+ status != BUSY_STATE &&
status != FINISH_STATE) {
return Z_STREAM_ERROR;
}
ss = source->state;
- *dest = *source;
+ zmemcpy(dest, source, sizeof(z_stream));
ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
if (ds == Z_NULL) return Z_MEM_ERROR;
dest->state = (struct internal_state FAR *) ds;
- *ds = *ss;
+ zmemcpy(ds, ss, sizeof(deflate_state));
ds->strm = dest;
ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
s->match_length = s->prev_length = MIN_MATCH-1;
s->match_available = 0;
s->ins_h = 0;
+#ifndef FASTEST
#ifdef ASMV
match_init(); /* initialize the asm code */
#endif
+#endif
}
#ifndef FASTEST
match = s->window + cur_match;
/* Skip to next match if the match length cannot increase
- * or if the match length is less than 2:
+ * or if the match length is less than 2. Note that the checks below
+ * for insufficient lookahead only occur occasionally for performance
+ * reasons. Therefore uninitialized memory will be accessed, and
+ * conditional jumps will be made that depend on those values.
+ * However the length of the match is limited to the lookahead, so
+ * the output of deflate is not affected by the uninitialized values.
*/
#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
/* This code assumes sizeof(unsigned short) == 2. Do not use
later. (Using level 0 permanently is not an optimal usage of
zlib, so we don't care about this pathological case.)
*/
+ /* %%% avoid this when Z_RLE */
n = s->hash_size;
p = &s->head[n];
do {
* of the string with itself at the start of the input file).
*/
#ifdef FASTEST
- if ((s->strategy < Z_HUFFMAN_ONLY) ||
+ if ((s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) ||
(s->strategy == Z_RLE && s->strstart - hash_head == 1)) {
s->match_length = longest_match_fast (s, hash_head);
}
#else
- if (s->strategy < Z_HUFFMAN_ONLY) {
+ if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
s->match_length = longest_match (s, hash_head);
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
s->match_length = longest_match_fast (s, hash_head);
* of window index 0 (in particular we have to avoid a match
* of the string with itself at the start of the input file).
*/
- if (s->strategy < Z_HUFFMAN_ONLY) {
+ if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
s->match_length = longest_match (s, hash_head);
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
s->match_length = longest_match_fast (s, hash_head);
return flush == Z_FINISH ? finish_done : block_done;
}
#endif /* FASTEST */
+
+#if 0
+/* ===========================================================================
+ * For Z_RLE, simply look for runs of bytes, generate matches only of distance
+ * one. Do not maintain a hash table. (It will be regenerated if this run of
+ * deflate switches away from Z_RLE.)
+ */
+local block_state deflate_rle(s, flush)
+ deflate_state *s;
+ int flush;
+{
+ int bflush; /* set if current block must be flushed */
+ uInt run; /* length of run */
+ uInt max; /* maximum length of run */
+ uInt prev; /* byte at distance one to match */
+ Bytef *scan; /* scan for end of run */
+
+ for (;;) {
+ /* Make sure that we always have enough lookahead, except
+ * at the end of the input file. We need MAX_MATCH bytes
+ * for the longest encodable run.
+ */
+ if (s->lookahead < MAX_MATCH) {
+ fill_window(s);
+ if (s->lookahead < MAX_MATCH && flush == Z_NO_FLUSH) {
+ return need_more;
+ }
+ if (s->lookahead == 0) break; /* flush the current block */
+ }
+
+ /* See how many times the previous byte repeats */
+ run = 0;
+ if (s->strstart > 0) { /* if there is a previous byte, that is */
+ max = s->lookahead < MAX_MATCH ? s->lookahead : MAX_MATCH;
+ scan = s->window + s->strstart - 1;
+ prev = *scan++;
+ do {
+ if (*scan++ != prev)
+ break;
+ } while (++run < max);
+ }
+
+ /* Emit match if have run of MIN_MATCH or longer, else emit literal */
+ if (run >= MIN_MATCH) {
+ check_match(s, s->strstart, s->strstart - 1, run);
+ _tr_tally_dist(s, 1, run - MIN_MATCH, bflush);
+ s->lookahead -= run;
+ s->strstart += run;
+ } else {
+ /* No match, output a literal byte */
+ Tracevv((stderr,"%c", s->window[s->strstart]));
+ _tr_tally_lit (s, s->window[s->strstart], bflush);
+ s->lookahead--;
+ s->strstart++;
+ }
+ if (bflush) FLUSH_BLOCK(s, 0);
+ }
+ FLUSH_BLOCK(s, flush == Z_FINISH);
+ return flush == Z_FINISH ? finish_done : block_done;
+}
+#endif
projects / opencv / blobdiff